Tuesday, November 20, 2007

Speed Limits and Road Safety

Local radio has reported several tragic accidents in the last few days on the roads of Herefordshire. Any death on our roads is one death to many and predictably there are calls for lower speed limits.

What should the speed limit be reduced to? A comment heard frequently is along the lines of “It’s a maximum speed, not a suggested speed”

Surely that is at the root of the problem. The more we try to set “safe” speed limits the more we take away the need for a driver to think for him/herself.

Inexperienced drivers must be forgiven for assuming that it is safe to drive at the posted limit because that is the world they have learnt to drive in. The modern attitude to health and safety is raising a generation that cannot recognise danger because it has always been sheltered from it. Young drivers are no different and observation suggests that the problem is not confined to the young.

So what should the speed limit be? The maximum safe speed on any stretch of road depends on the road surface, the visibility, the volume of traffic, the ability of the driver and the condition of the vehicle. No authority can possibly set a limit that is correct for all the possible variables so it could be argued that the limit must be low enough to allow for every eventuality.

OK, let’s assume an old car, poorly maintained, driven by a seventeen year old who has just passed their test. The road is covered with ice and fog has reduced visibility to 30 metres.

Maximum safe speed is zero. So logically the only way to set speed limits to stop accidents is to ban vehicles from moving.

Much better to remove all speed limits. Those who can learn to drive will do so and survive. Those that can't learn won’t be able to get insured!

Sunday, October 28, 2007

How green are hybrid cars?

Hybrid cars use batteries and electric motors to achieve zero emissions when running solely on battery power. They also have a conventional internal combustion engine, usually petrol driven, that can also propel the car or re-charge the batteries or both.

If the batteries are re-charged from an external power supply there is no point in having the petrol engine and energy is being wasted hauling it around. If the batteries are recharged by the in-built engine then energy is being wasted hauling the batteries around.

At best these vehicles only move pollution out of the most congested areas, either to the power station or to less congested roads. The basic laws of science dictate that they cannot be more energy efficient then either a straight internal combustion powered car of the same carrying capacity or a solely battery powered car of the same carrying capacity.

What do you think?

Friday, July 27, 2007

4x4 Vehicle safety

It’s been very wet round here recently with some areas experiencing their worst floods for over sixty years. As you might expect there are tales of selfless effort and other tales of total selfishness. On the one hand there were drivers with large 4wd vehicles who went out of their way to help others and then there were the few who ignored the needs of others and drove their vehicles with no regard for anyone or anything.

This got me thinking about the general safety of 4wd vehicles and I came to what I think is an interesting conclusion.

4wd vehicles are inherently less safe than 2wd vehicles.

Ignoring all the psychobabble about feeling safer in a larger vehicle which I don’t understand, this is my theory.

Stopping a vehicle from any speed requires that the energy stored by getting the vehicle up to that speed must be expended. The amount of stored energy is determined by the speed of the vehicle and its weight.

For any given speed, a heavier vehicle will have to get rid of more energy than a lighter vehicle. The energy goes into heating up the brakes, tyres and even the road surface and also in a certain amount of noise in some cases.

4wd and 2wd vehicles have the same number of brakes, so there is no difference there. The difference between the two types is the number of wheels that take power from the engine, either 2 or 4. To take power from the engine to an extras pair of wheel requires at least one, probably two, extra differentials and their drive shafts. These are heavy pieces of kit and add quite a lot of weight.

So we now have a heavier vehicle which is not as easy to stop, but the same number of brakes. On top of this the 4wd vehicle is capable of building up speed in conditions that would defeat 2wd. So we have the situation that a 4wd vehicle is easier to drive into trouble and then less able to stop.

2wd or 4wd, drive carefully out there.

Thursday, December 07, 2006

Donna Nook

When I saw the TV programme about Donna Nook I thought it looked too good to be true.

This week we went to see for ourselves.

This has to be a unique nature reserve, in the UK at least. The foreshore is used by the Ministry of Defense as an aerial gunnery and bombing range and by Atlantic Grey Seals as a breeding rookery.

There are seals and seal pups all over the beach, right up to the low fence at the foot of the sand dunes. Visitors to the reserve are told to avoid unexploded ordnance and not to touch the seals. We had no problem with ordnance but it was very tempting to touch a seal pup to feel how soft the fur is.

There are notices warning visitors that touching the pups could lead to their rejection by their mothers and pointing out that they can bite. One pup yawned close by and showed its teeth and the warning notices made a lot of sense. Lots of very sharp teeth!

The seal pup pictured is just weaned, about three weeks old and double its birth-weight. Its mother will probably have mated and gone back to sea. The pup will moult its white fur over the next few days and will then head out to sea. The photo was taken on a Minolta DiMage Xi through the gaps in the fence, no zoom needed. Some pups actually sleep with their noses against the fence but this one was a few feet away.

An amazing experience, well worth driving 400 miles to see.

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Monday, November 20, 2006

Bodenham Arboretum

I've been very busy for weeks now, working on the mill restoration and the mill web-site as well as my own recipe web-site.

On Saturday the sun was shining and the day was clear and crisp so we decided to check out the autumn colours at Bodenham Arboretum. The very first photo I took turned out to be the best of the bunch so I thought I'd post it here.

Friday, October 13, 2006

A Happy Event

When the phone rings in the middle of the night it is a bit scary but this time it was good news.

Felix Richard John Gallé was born on Friday 13th October, weighing in at 7 1/2 pounds with strawberry blonde hair. Our first grandchild!

Both mother and baby are doing well in hospital in Toulouse.

Friday, October 06, 2006

A different afternoon

We checked the weather forecast this morning and decided that it looked like a good day for staying at home. So we didn't. We spent the afternoon at WWT Slimbridge watching wildfowl.

It's our way of avoiding the crowds and it works. Most of the time we had the Holden Tower hide to ourselves with views across the Severn estuary only occasionally obscured by driving rain. There is something very cosy about sitting somewhere dry and secure and watching nasty weather go by outside.

There were a lot of Canada Geese and Barnacle Geese on the marshes with a pair of Greylag Geese. We could see waders on the Severn mud but they were too far away for easy identification, just possibly Bar-tailed Godwits.

On our way to the Holden Hide we stopped of at South Hide and had a close encounter of the Scipidae kind. A different slant on bird watching!